Helm chart testing enhancement

[RainbowMango]

What would you like to be added:

1. Make images based on PR or the latest code and then test with them
2. Make sure to cover all components

Why is this needed:

Currently, helm testing does not test against the latest code but the last images on image registry. When we introduce new parameters to a component the chart test will fail due to unrecognized parameters, see the example here: #5290 (comment).

In addition, the helm chart test coverage is not enough, it just tests part of the components, for example, the karmada-scheduler-estimator is not included in the test, that's why it passes #5273.

[RainbowMango]

May be #4045 addresses part of this.

[chaosi-zju]

here is another shortage I want to raise:

karmada-scheduler-estimator has installation problem when installMode=component.

just like:

I firstly execute helm install karmada -n karmada-system to install karmada main components.

then all karmada certs is stored in secret/{{.Release.Name}}-cert, since {{.Release.Name}} is karmada, so secret name is karmada-cert.

karmada/charts/karmada/templates/pre-install-job.yaml

Lines 249 to 253 in 295dee8

	apiVersion: v1
	kind: Secret
	metadata:
	name: {{ $name }}-cert
	namespace: {{ $namespace }}

Then I execute helm install karmada-scheduler-estimator -n karmada-system --set installMode=component,components={"schedulerEstimator"} to install scheduler estimator independently.

the estimator needs to mount that secret/{{.Release.Name}}-cert to obtain karmada certs, however, now {{.Release.Name}} is karmada-scheduler-estimator (host cluster does not allow duplicate release names), so it will try to mount secret/karmada-scheduler-estimator-cert, which doesn't exist.

karmada/charts/karmada/templates/_helpers.tpl

Lines 352 to 356 in 295dee8

	{{- define "karmada.scheduler.cert.volume" -}}
	{{ $name := include "karmada.name" . }}
	- name: karmada-certs
	secret:
	secretName: {{ $name }}-cert

---

---

Actually, metricsAdapter,search,descheduler when installMode=component has same problem, the original author gives a rough circumvention:

karmada/charts/karmada/values.yaml

Lines 969 to 972 in 295dee8

	## @param search.certs certs of the search
	certs: karmada-cert
	## @param search.kubeconfig kubeconfig of the search
	kubeconfig: karmada-kubeconfig

that is, redeclare the secret name in value.yaml to overwrite the original {{.Release.Name}}-cert.

but I think the best way is fix the secret name, don't prefix it with {{.Release.Name}}, which is mentioned in #5363.